Saturday, September 28, 2024

The First Known Exoplanet (all night)

In the eastern sky on starry September evenings, look for a dim star shining
a thumb's width just outside of the baseball diamond shape of Pegasus' Great Square, midway between the top and right corners. That yellow, sunlike star named Helvetios (or 51 Pegasi) is orbited by the first exoplanet ever discovered, in 1995. The planet, which orbits that star every 4.23 days at a distance much closer to the star than Mercury does in our solar system, is categorized as a Hot Jupiter type. Originally nick-named Bellerophon, one of the original riders of Pegasus in Greek mythology, the planet is now
officially named Dimidium, the Latin word for "half" - since the planet has half the mass of Jupiter.

(Data Courtesy of Starry Night)
--- SBBSecho 3.20-Linux
* Origin: CJ's Place, Orange City FL > cjsplace.thruhere.net (21:2/156)